<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>IFC</title>
    <style>
        /*IFC的元素会在一行中从左至右排列*/
        span {
            font-size: 30px;
            background-color: #f4ff57;
            /* width: 200px;!*行级标签不识别宽高*!
             display: inline-block;!* 如果要让行标签识别宽高，必须用display把设成块级标签 *!*/
        }

        strong {
            font-size: 16px;
            background-color: #ffadf5;
            vertical-align: top;
        }

        .box {
            float: left;
            font-size: 50px;
        }

        div {
            display: inline;
        }
    </style>
</head>
<body>
<span>span</span>
<strong>strong</strong>
<em class="box">box</em>
<div>div</div>
</body>
</html>